The present invention relates to a measuring device at recovery devices, wherein the recovery device is designed for location locally in workshops or similar premises, in which contaminated or impure solvent originates because objects in the workshops or similar premises are cleaned by means of a solvent. The recovery device includes a container for contaminated or impure solvent, a heating device for heating contaminated solvent present in the container, such that solvent vapours are generated in the container, and a condenser for condensing solvent vapours which are fed from the container to the condenser for condensing the solvent vapours therein to pure solvent which is fed to a container for pure solvent.
At recovery devices for recovering pure solvent (i.e., thinner from contaminated solvent, impure solvent, colorants, or oils, etc.), the recovered pure solvent is fed to a container which will be emptied when it is full. However, it has happened that the recovery device is started for recovering pure solvent without previously having emptied or substantially emptied the container with pure solvent. This has resulted in that the container has been overfilled such that solvent has run out. This is quite unacceptable because many solvents, e.g. thinner, as well as their vapours are injurious to health.
The object of the present invention is to eliminate this problem or at least to acknowledge the problem such that the required measures can be taken. Since the measuring device comprises a capacitive detector which is provided to detect or sense if the container for pure solvent is empty or substantially empty or not, and to signal if the container is not empty or substantially empty, it is possible, without movable components, with simple, precise and reliable means which also withstand aggressive solvents, to generate warning signals or even block starting if one tries to start the recovery device without first having emptied or substantially emptied the container for pure solvent. The capacitive detector further permits detection of difficult to detect liquids such as e.g. thinner.